Shufflebrain

Many of us first became acquainted with the word wave when someone hoisted us from the crib or playpen, gently kissed us on the side of the head, and coaxed, "Wave bye-bye to Uncle Hoibie!" Later, we may have thought "wave" as we pressed a nose against the cool windowpane and watched little brother Ben's diapers waving on the clothesline in the autumn breeze. Then one Fourth of July or Saint Patrick's Day, our mother perhaps gave us a whole quarter; we ran to the candy store on the corner, and, instead of baseball cards and bubble gum, we bought a little American flag on a stick. We ran over to the park and waved the little flag to the rhythm of the march; then we began to laugh our heads off when the mounted policemen jiggled by in their saddles, out of time with each other and the beat of the drums and the cadence we were keeping with the little waving flag. Still later, perhaps, we learned to wave Morse code with a wigwag flag, dot to the right, dash to the left. Up early to go fishing, when radio station W-whatever-the-heck-it-was signed on, we may have wondered what "kilocycles" or "megahertz" meant. And it was not until after we began playing rock flute with the Seventh Court that the bearded electronic piano player with the Ph.D. in astronomy said that "cycle" to an engineer is "wavelet" to a sailor, and that the hertz value means cycles per second--in other words, frequency. If we enrolled in physics in high school, we probably carried out experiments with pendulums and tuning forks. An oscillating pendulum scribed a wave on a smoked, revolving drum. A vibrating tuning fork also created waves, but of higher frequency: 256 cycles per second when we used the fork with the pitch of middle C on the piano. Moving down an octave, according to the textbook, would give us 128 hertz.

Are our usages of wave metaphorical? The word metaphor has become overworked in our times. While I certainly wouldn't want to deny waves to poets, I don't think metaphor is at the nexus of our everyday usage of wave . Analog is a better choice: something embodying a principle or a logic that we find in something else. (Notice the stem of analog.)

To and fro, rise and fall, up and down, over and under, in and out, tick and tock, round and round, and so on... Cycles. Periodicities. Recurrences. Undulations. Corrugations. Oscillations. Vibrations. Round-trip excursions along a continuum, like the rise, fall, and return of the contour of a wavelet, the revolutions of a wheel, the journey of a piston, the hands of a clock. These are all analogs of waves.

Do we really mean that pendular motion is a symbolic expression of the rotations of a clock's hands? No. The motion of one translates into continuous displacements of the other. Is the ride on a roller coaster an allegorical reference to the course of the tracks? Of course not. The conduct of the one issues directly from the character of the other, to borrow a phrase from a John Dewey title. And why would we suppose that a pendulum or a tuning fork could scribe a wave? The answer is that the same logic prevails in all periodic events, patterns, circumstances, conditions, motions, surfaces, and so forth.

No, a child's hand isn't the same thing as a fluttering piece of cloth or the ripples on a pond. And yes, there's imprecision and imperfection in our verbal meanings; we wouldn't want it otherwise. Poetry may exist in all of this. Yet by our literal usages of wave we denote what Plato would have called the idea of waviness, the universal logic revealed by all things wavy. And that logic translates, completely, into amplitude and phase. And if the medium stores phase information, we have a species of hologram.

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Not all physics is about waves, of course. The liveliest endeavor in that science today, the pursuit of the quark, is a search for fundamental particles -- discrete entities -- of mass-energy. The photon is a light particle. Light is both particles and waves. The same is true of all mass-energy at the atomic level. The electron microscope, for example, depends on electrons, not as the particles we usually consider them to be but as the electron waves uncovered in the 1920s as the result of de Broglie's theories. And one of the tenets of contemporary physics is that mass-energy is both particulate and wavy. But when we are dealing with particles, the wavy side of mass-energy disappears; and when it is measured as waves, mass-energy doesn't appear as particles. If you want to concentrate on corpuscles of light, or photons, you must witness the transduction of a filament's mass-energy into light, or from light into some other form, as occurs in the quantized chemical reactions in our visual pigment molecules. But if the choice is light on the move between emission and absorption, the techniques must be suitable for waves.